Environmental Impact of Approving Biomass Conversion Plants in California. California State Senate Office of Research

Transcription

1 Environmental Impact of Approving Biomass Conversion Plants in California presented to the August 26, 2013 Prepared by: Renewable Energy Institute California Polytechnic State University 1 Grand Avenue San Luis Obispo, CA Dr. Thomas Korman, PE Associate Professor tkorman@calpoly.edu Lonny Simonian, PE Associate Professor lsimonia@calpoly.edu Laura Radle Graduate Student lradle@calpoly.edu Margot McDonald, AIA Director, REI mmcdonal@calpoly.edu

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3 Table of Contents LIST OF TABLES... iii LIST OF FIGURES... v Executive Summary... 1 Section 1 Introduction Purpose and Scope Background... 3 Section 2 Existing Biomass Technologies and Plants in California Existing Biomass Technologies Combustion Co firing Gasification Pyrolysis Anaerobic digestion Commercial Bioenergy routes Existing Biomass Energy Plants in California... 8 Section 3 Survey of Existing Biomass Feedstocks First Generation Feedstocks Second Generation Feedstocks Section 4 Feedstock Analysis Phase 1: Feedstock Types Phase 2: Management and Procurement Phase 3: Transportation Phase 4: Energy Generation Technology Fuel Analysis Approach for Estimating CO 2 Emissions: Phase 5: Timeframe to Replenish Feedstock CO 2 Emissions of the Biopower Pathway Environmental Impact of Approving Biomass Conversion Plants in California Page i

4 Section 5 Net Reduction to CO2 emissions and Economic Feasibility Net Reduction to CO 2 emissions Economic Feasibility References APPENDIX A Calculation Spreadsheets Environmental Impact of Approving Biomass Conversion Plants in California Page ii

5 LIST OF TABLES Table 3 1 Estimated Quantity and Potential Energy Value of First Generation Feedstocks Table 3 2 Quantity and Energy Value of Second Generation Feedstocks Table 4 1 CO 2 Emissions for Phase 1: Feedstock Types (from Figure 1) Table 4 2 CO 2 Emissions for Phase 2: Management and Procurement (Establishment/Maintenance and Harvest/Storage from Figure 4 1) Table 4 3 CO 2 Emissions for Phase 3: Transportation (from Figure 4 1) Table 4 4 CO 2 Emissions for Co Firing, Direct Combustion and Gasification Technologies Table 4 5 CO 2 Emissions for Phase 5: Timeframe to Replenish Feedstock Table 4 6 CO 2 Emissions of the Biopower Pathway (kg CO 2 eq./ton) Table 5 1 California In State Electricity Generation Table 5 2 Cumulative Fuel Cost Calculation based on % Electricity Produced by California Table 5 3 Economic Feasibility Table 5 4 Carbon Neutral Biomass Feedstocks and Subsidies Environmental Impact of Approving Biomass Conversion Plants in California Page iii

6 Environmental Impact of Approving Biomass Conversion Plants in California Page iv

7 LIST OF FIGURES Figure 2 1 Commercial Bioenergy routes (Chum, H. et. al. 2011)... 7 Figure 2 2 Lifecycle CO 2 Emissions (Chum, H. et. al. 2011)... 7 Figure 2 3 Map of Existing Biomass Plants in California (Mayhead, 2012)... 8 Figure 4 1 GHG Emissions per dry ton (Daystar, 2012) Figure 4 2 Basis for Fuel Analysis Calculations Environmental Impact of Approving Biomass Conversion Plants in California Page v

8 Environmental Impact of Approving Biomass Conversion Plants in California Page vi

9 Executive Summary Generating electricity from biomass is considered to be an alternative energy source due to its promise to reduce the quantity of CO 2 released into the environment, when compared with fossil fuels. However, biomass is considered to be a low density fuel, because it is believed to be more expensive than fossil fuels to produce, handle, and transport. The purpose of this study was to analyze whether or not exclusive use of feedstocks/technologies that are carbonneutral would be economically feasible for biomass plant operators, or under what circumstances (i.e., subsidies and/or incentives) economic feasibility could be achieved. Determining the economic feasibility for the biomass feedstocks available in California involved comparing the average cost of biomass fuel against the cumulative cost of fuel of California s current energy generation technologies. Published data indicates that the majority of electricity produced in the state of California is generated from natural gas. The balance of is produced from nuclear, large hydro, renewables, and coal. Using a weighted average calculation, the cumulative cost of fuel was determined to be $6.56 US dollars per MMBtu. This value was used as the baseline for comparison to determine whether or not an individual biomass feedstock is economically feasible. Based on prior research, a life cycle analysis methodology that considers carbon emissions throughout the life cycle of a feedstock was used to calculate the average fuel cost for each feedstocks. This was performed for all feedstocks that are definitively able to provide carbon neutrality or net reductions to carbon emissions. A comparison for each feedstock was then performed against California s current energy cumulative cost. Findings indicate that most of the first generation feedstocks, which include orchard pruning s and vine removal, field and seed, vegetable trimmings, food processing (rice hulls, shells, and pits), mill residue, logging slash, chaparral, municipal solid waste were determined to have an average fuel cost below $6.56 and therefore do not require a subsidy. Several of the second generation feedstocks, which include loblolly pine, eucalyptus, sugarcane/energycane, sugarcane bagasse, and algae were calculated to have a fuel cost average of $5.96 US dollars per MMBtu, which approaches the limit of $6.56 US dollars per MMBtu for economic feasibility. These biomass feedstocks may require subsidies under circumstances that vary from the analyzed conditions in this report. The calculation for forest thinnings yielded an average fuel cost of $7.78 US dollars per MMBtu, which is not economically feasible, and would require a subsidy of at least $1.22 US dollars per MMBtu to be competitive. The calculation for animal manure also indicated that it is not economically feasible primarily due to the fact that manure biogas systems are typically very small for gas treatment to be economical. Environmental Impact of Approving Biomass Conversion Plants in California Page 1

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11 Section 1 Introduction 1.1 Purpose and Scope The purpose of this study was to prepare information for state decisions makers regarding the Environmental Impact of Approving Biomass Conversion Plants in California. The scope of work included the following: 1. Reviewing existing literature on comprehensive life cycle assessments of biomass toenergy projects in the Western United States; 2. Identifying feedstocks and/or technologies in current or future use that definitively provide carbon neutrality or net reductions to carbon emissions when all life cycle emissions are considered; 3. Analyzing whether exclusive use of feedstocks/technologies that are carbon neutral would be economically feasible for biomass plant operators, or under what circumstances (subsidies/incentives) economic feasibility could be achieved; and 4. Determine whether increased use of biomass conversion to contribute to California's Renewable Portfolio Standard is warranted. 1.2 Background The generation of electricity from biomass is considered by some to be an alternative source of energy production due to its ability to reduce the amount of CO 2 released into the environment when compared against fossil fuels. However, biomass is a considered to be a low density fuel, meaning that it is considered to be more expensive than fossil fuels in production, handling, and transportation. Another factor differentiating biomass fuels from fossil fuels is that emissions from biomass to the biosphere are reversible whereas those from fossil fuel sources are not (Sedjo, 2011). The primary sources of biomass found throughout the State of California include agricultural, forestry, and municipal. As a whole, the sources of biomass energy feedstocks are considered to be scarcer and more dispersed when compared to fossil fuels. In addition, the existing biomass power generating facilities are relatively small when compared to fossil fuel energy production facilities. Therefore, the generation of electricity from biomass appears to be at a disadvantage (Morris, 1999). According to Morris, the value of the environmental services associated with biomass energy production in the United States is 14.1 /kwh (Morris, 1999). The calculation Morris uses to generate this value takes into consideration both electric and non electric benefits. His methodology includes the development of the economy in rural, including related employment and the increase of energy generation diversification and security provided by biomass energy production. Environmental Impact of Approving Biomass Conversion Plants in California Page 3

12 According to Morris, there have been a number of policies that have been proposed to enhance the viability of biomass energy generation in California. These policy goals focus upon providing enough incentives to preserve and expand the production of renewable biomass energy in California (Morris, 2002). Prior research indicates that the establishment of payments would cover the cost associated with establishing these crops (i.e., clearing, planting, and seeding) within a project area (Stubbs 2010). Federal congressional support for biopower has aimed to promote energy security and has generally assumed that biopower is carbon neutral (Bracmont, 2011). However, determining whether or not biopower is carbon neutral depends on the following (Bracmont, 2011): feedstock type electricity generation technology used, and time frame examined. Furthermore, energy production activities are generally classified as carbon neutral if they do not produce or do not increase the amount of greenhouse gas (GHG) emissions when the entire life cycle is considered. This calculation considers the carbon flux, which is the CO 2 emission and sequestration at each phase of the biopower pathway. The carbon flux varies considering the specific site and method used to produce electricity. In work completed by Miner, he states the following regarding the carbon neutrality of biomass energy (Miner 2010): Biomass energy is carbon neutral because biomass is naturally carbon neutral; Biomass energy is neutral if the activity removes as much CO2 as was emitted into the atmosphere; Biomass energy is neutral only if the net life cycle emissions are zero; and Biomass energy is neutral if it achieves lower net increases in atmospheric GHG s when compared to alternative energy activities. In order to evaluate the economic feasibility of producing energy with biomass a Life Cycle Analysis (LCA) is needed that calculates the environmental footprint and includes the carbon flux of a particular biopower pathway. This requires following each biomass fuel sources from a point of origin to the point where electrical energy is generated. Bracmort argues that only an LCA for each biopower operation can truly determine whether biopower generation is carbon neutral and a complete LCA will measure carbon flux for each phase of the biopower pathway and incorporates the replenishment of the individual biomass feedstock. A standard approach in performing a biopower LCA ensures uniformity in carbon accounting across the biopower sector (Bracmort, 2011). Environmental Impact of Approving Biomass Conversion Plants in California Page 4

13 Section 2 Existing Biomass Technologies and Plants in California 2.1 Existing Biomass Technologies There are many technologies that can be employed to convert biomass feedstocks to electric energy. The primary technologies include combustion, co firing, gasification, pyrolysis, and anaerobic digestion. Each of these processes is summarized below Combustion Combustion is the burning of biomass in a power plant. The biomass is burned to heat a boiler and create steam. The steam powers a turbine, which is connected to a generator to produce electricity. Existing plant efficiencies are in the low 20% range, although methods could be employed to advance efficiency above 40%. Efficiency refers to that percentage of a feedstock that is actually converted to electricity (i.e., electricity energy output/feedstock energy input). Approximately 180 combustion units across the United States for biomass are in operation using wood and agricultural residues as the feedstock (Bracmort, 2010) Co firing Co firing is the simultaneous firing of biomass with coal in an existing power plant; it is considered to be the most cost effective biopower technology (Bracmont 2010). Co firing with biomass uses existing equipment and is less expensive than constructing a new biopower plant. Although existing plants require retrofitting to accept the biomass entering the plant, certain air particulates associated with coal combustion are reduced with co firing, as less coal is being burned. Co fired plants have efficiencies ranging from 33% to 37%, while coal fired plants have efficiencies ranging from 33% to 45%. Approximately seventy eight (78) co fired biomass units that use wood or other agricultural residues as feedstocks are in operation throughout the United States (Bracmort, 2010) Gasification Gasification is the heating of biomass into a synthetic gas, known as syngas, in an environment with limited oxygen. Syngas is a mixture of hydrogen and carbon monoxide, which is highly flammable. Syngas can then be used in a combined gas and steam turbine to generate electricity with efficiencies ranging from 40% to 50%. One challenge for gasification is feedstock logistics (e.g., cost to ship or transport the feedstock to the power plant). A wide variety of feedstocks could undergo gasification, including wood chips, sawdust, bark, agricultural resides, and waste; however, there are currently no gasification systems for biomass at any scale (Bracmort, 2010). Environmental Impact of Approving Biomass Conversion Plants in California Page 5

14 2.1.4 Pyrolysis Pyrolysis is the chemical breakdown of a substance under extremely high temperatures in the absence of oxygen. These temperatures range from 400 C to 500 C. There are currently two types of pyrolysis technologies, fast and slow. Fast pyrolysis technologies can be used to generate electricity by producing a liquid product from a biomass feedstock; this pyrolysis oil or bio oil can be readily stored and transported. The bio oils produced from these technologies are suitable for use in boilers for electricity generation. A major challenge for the pyrolysis technology is that the bio oil produced tends to be of lower quality relative to what is needed for power production. Feedstock types for pyrolysis include a variety of wood or agricultural resources. Currently, there are no commercial scale pyrolysis facilities utilizing biomass in the United States (Bracmort, 2010) Anaerobic digestion Anaerobic digestion is a biological conversion process that breaks down a feedstock (e.g., manure, landfill waste) in the absence of oxygen to produce methane and other gases that can be captured and used as an energy source to generate electricity. Anaerobic digestion systems have historically been used for comparatively smaller scale energy generation in rural areas. Feedstocks suitable for digestion include brewery waste, cheese whey, manure, grass clippings, restaurant wastes, and the organic fraction of municipal solid waste, among others. Generation efficiency ranges from 20% to 30% (Bracmort, 2010) Commercial Bioenergy routes The Figures 2 1 and 2 2 (Chum, H. et. al. 2011) graphically display a variety of bioenergy conversion routes and their associated lifecycle CO 2 emissions. For example, as shown in Figure 2 1, the conversion of Oil Crops to energy can follow two conversion routes leading to the generation of liquid fuels such as biodiesel and renewable diesel. Through the conversion path of transesterification or hyrdogenenation, either biodiesel of renewable diesel can be generated. In addition, when oil crops are combined with lignocellulosic biomass through the combustion conversion route, either heat and/or power can be generated. Environmental Impact of Approving Biomass Conversion Plants in California Page 6

15 Figure 2 1 Commercial Bioenergy routes (Chum, H. et. al. 2011) Figure 2 2 Lifecycle CO 2 Emissions (Chum, H. et. al. 2011) Environmental Impact of Approving Biomass Conversion Plants in California Page 7

16 2.2 Existing Biomass Energy Plants in California There are currently thirty three (33) active and operating energy plants generating electricity from biomass feedstocks located throughout California. Figure 2 3 (Mayhead, 2012) graphically displays the location and capacity of these plants. Reference: Mayhead, 2012 Figure 2 3 Map of Existing Biomass Plants in California (Mayhead, 2012) Environmental Impact of Approving Biomass Conversion Plants in California Page 8

17 Section 3 Survey of Existing Biomass Feedstocks Biomass feedstocks are generally divided into two categories, first and second generation. Those feedstocks that are widely grown and used for some form of production are known as first generation feedstocks. Second generation feedstocks generally refers to crops that have a high potential yield of biofuel, but that may not be widely cultivated, or may not be cultivated as an energy crop. 3.1 First Generation Feedstocks First generation feedstocks represent biomass that is currently available. Tables 3 1 and 3 2 were generated by consolidating data from several sources. As shown, California produces an estimated eight six (86) million tons of biomass annually (Moller, 2005). Approximately thirtythree and two thirds (33.6) million tons is estimated to be technically feasible to be collected and used in producing renewable electricity, fuels, and biomass based products (Moller, 2005). About 30% of this amount could come from agriculture, 40% from forestry, and another 30% could be recovered from municipal sources, including landfill gas and biogas (methane) from wastewater treatment. Environmental Impact of Approving Biomass Conversion Plants in California Page 9

18 Table 3 1 Estimated Quantity and Potential Energy Value of First Generation Feedstocks First Generation Feedstocks Total Biomass Produced (million dry tons/yr) Biomass That Can Effectively Be Utilized (million dry tons/yr) Energy Value Btu/lb (dry) Average Energy Value / Appendix A, Table 13 Reference Moller, 2005 Moller, 2005 Appendix A, Table 13 First Generation Feedstocks ,929 18,443 Agricultural ,125 18,898 Animal Manure ,500 19,771 Orchard Pruning & Vine Removal ,825 18,200 Total Field and Seed ,825 18,200 Total Vegetable ,825 18,200 Total Food Processing ,650 20,120 Forestry ,570 19,934 Mill Residue ,570 19,934 Forest Thinnings ,570 19,934 Logging Slash ,570 19,934 Chaparral ,570 19,934 Municipal ,093 16,498 Notes: 1) BTU/lb = KJ/kg conversion factor References: Moller, 2005; Appendix A, Fuel Analysis Spreadsheet Environmental Impact of Approving Biomass Conversion Plants in California Page 10

19 3.2 Second Generation Feedstocks As stated above, second generation feedstocks include crops that have high potential yields of biofuels, but that may not be widely cultivated, or may not be cultivated as an energy crop. These feedstocks include grasses, trees, and algae. The table below lists second generation feedstocks and their corresponding energy value in Btu/lb dry and KJ/kg dry. Table 3 2 Quantity and Energy Value of Second Generation Feedstocks Second Generation Feedstocks Average Energy Value Btu/lb (dry) Average Energy Value / Loblolly Pine 8,560 19,911 Eucalyptus 8,303 19,313 Unmanaged Hardwood 6,150 14,305 Switchgrass 8,670 20,166 Miscanthus 8,250 19,189 Sugarcane/Energycane 7,900 18,374 Wheat Straw 6,840 15,910 Sugarcane Bagasse 7,900 18,374 Algae (algal mass) 9,000 20,934 Algae (algal oil and lipids) 16,000 37,216 Notes: 1) BTU/lb = KJ/kg conversion factor References: Appendix A, Fuel Analysis Spreadsheet Environmental Impact of Approving Biomass Conversion Plants in California Page 11

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21 Section 4 Feedstock Analysis Using federal and state government databases, we identified feedstocks and technologies that provide carbon neutrality and/or net reductions to carbon emissions when all life cycle emissions are considered. We organized these feedstock and technologies by focusing upon net carbon emissions when the entire life cycle of the process is considered. Finally, we determined the carbon neutrality/net reduction to carbon emission factors for each phase of the biomass pathway. The Society of Environmental Toxicology and Chemistry defines a Life Cycle Analysis (LCA) as an objective process to evaluate the environmental burdens associated with a product, process, or activity by identifying energy and materials used and wasted released to the environment, and to evaluate and implement opportunities to affect environmental improvements (Consoli et al. 1993), (USDA, 2005). LCA can be used to assess environmental impacts associated with all the stages of a product s life from cradle to grave (i.e., from raw material extraction through materials processing, manufacture, distribution, use, repair and maintenance, and disposal or recycling). A LCA can function as a tool to avoid a narrow outlook on environmental concerns by utilizing calculations in the environmental footprint, including the carbon flux of a particular biopower pathway. Carbon neutrality for biopower can be most accurately calculated based on the carbon flux (CO 2 emission or sequestration) of several parameters of a specified time period. In this report, we focused on the following five (5) phases of the biopower pathway (with each phase representing a stage in time with different CO 2 emissions): Phase 1: Feedstock Type Phase 2: Management and Procurement Phase 3: Feedstock Transportation Phase 4: Energy Generation Technology Phase 5: Time to Replenish Feedstock The following subsections summarize our findings using LCA for both first and second generation feedstocks and focus upon identifying feedstocks available in California that definitively provide carbon neutrality or net reductions to carbon emissions when all life cycle emissions are considered. Environmental Impact of Approving Biomass Conversion Plants in California Page 13

22 4.1 Phase 1: Feedstock Types The biomass feedstock type is often the most important contributor to the net reductions in carbon emissions over the biopower pathway. Figure 4 1 illustrates the greenhouse gas emissions per dry ton in different phases of the biopower pathway [including biomass growth (Phase 1), establishment/maintenance and harvest/storage (Phase 2), and transportation (Phase 3)] for a diverse range of feedstocks. Notice that the Biomass Growth column is the largest input to the net reduction in carbon emissions. The negative estimates within the terminology of lifecycle assessments presented in this report refer to avoided emissions, without consideration of energy generation (which is included in Table 4 4). Figure 4 1 only represents Phase 1, 2 and 3 of the biopower pathway and does not include net emissions for Phase 4 and Phase 5 of the biopower pathway defined previously in the report. Reference: Daystar, J., Reeb, C., Gonzalez, R., Venditti, R., Kelley, S. (2012). Figure 4 1 GHG Emissions per dry ton (Daystar, 2012) Environmental Impact of Approving Biomass Conversion Plants in California Page 14

23 The values in Figure 4 1 are used as a guideline for the biomass feedstocks analyzed in this report. The feedstocks listed in Table 4 1 were examined in order to identify feedstocks and/or technologies that definitively provide carbon neutrality or net reductions to Carbon emissions when all life cycle emissions are considered. The feedstock types include both first and second generation feedstocks and were selected 1. on existing biomass availability in the state of California and 2. on future biomass potential in California. Table 4 1 lists the net reduction to CO 2 emissions consistent with the values given in Figure 4 1. Environmental Impact of Approving Biomass Conversion Plants in California Page 15

24 Table 4 1 CO 2 Emissions for Phase 1: Feedstock Types (from Figure 1) Feedstock Types CO 2 Emissions for Phase 1 (kg CO 2 eq./ton) TOTAL Biomass Feedstocks 34,051 First Generation Feedstocks 16,201 Agricultural Biomass 7,200 Animal Manure 1,800 Orchard Pruning s and Vine Removal 1,800 Field and Seed 1,800 Vegetable Food Processing (rice hulls, shells, and pits) 1,800 Forestry Biomass 7,202 Mill Residue 1,800 Forest Thinnings 1,800 Logging Slash 1,800 Chaparral 1,800 Municipal Biomass 1,800 Municipal Solid Waste 1,800 Second Generation Feedstocks 17,849 Loblolly Pine 1,800 Eucalyptus 1,800 Unmanaged Hardwood 1,750 Switchgrass 1,700 Miscanthus 1,800 Sugarcane/Energycane 1,800 Wheat Straw 1,800 Sugarcane Bagasse 1,800 Algae (algal mass) 1,800 Algae (algal oil and lipids) 1,800 Notes: 1. Direct value from Integrated Supply Chain NC State University, (Daystar, J. et. al. 2012) 2. Assumed value based on Integrated Supply Chain NC State University, (Daystar, J. et. al. 2012) 3. Vegetable crop residues are considered negligible for purposes of this report because the total biomass that can effectively be utilized (million dry tons/yr) is only 0.1 as represented in Table 1. Vegetable crop residues are not generally considered for off field utilization and are commonly incorporated into the soil, (Moller, 2005). Reference: Daystar, J., Reeb, C., Gonzalez, R., Venditti, R., Kelley, S. (2012). Environmental Impact of Approving Biomass Conversion Plants in California Page 16

25 4.2 Phase 2: Management and Procurement Management and procurement includes CO 2 emissions associated with the establishment, maintenance, harvest and storage of the feedstock. The state of California has relatively low CO 2 emissions associated with the management and procurement of biomass feedstocks because the biomass energy industry is already well established for agricultural biomass throughout the Central Valley and for forestry biomass in Northern California. Table 4 2 shows a small increase to CO 2 emissions during the Phase 2: Management and Procurement stage based upon the values given in Figure 4 1. Environmental Impact of Approving Biomass Conversion Plants in California Page 17

26 Table 4 2 CO 2 Emissions for Phase 2: Management and Procurement (Establishment/Maintenance and Harvest/Storage from Figure 4 1) Feedstock Types CO 2 Emissions for Phase 2 (kg CO 2 eq./ton) TOTAL Biomass Feedstock 705 First Generation Feedstocks 185 Agricultural Biomass 75 Animal Manure 15 Orchard Pruning s and Vine Removal 15 Field and Seed 15 Vegetable Food Processing (rice hulls, shells, and pits) 15 Forestry Biomass 60 Mill Residue 15 Forest Thinnings 15 Logging Slash 15 Chaparral 15 Municipal Biomass 50 Municipal Solid Waste 50 Second Generation Feedstocks 520 Loblolly Pine 40 Eucalyptus 50 Unmanaged Hardwood 15 Switchgrass 115 Miscanthus 50 Sugarcane/Energycane 50 Wheat Straw 50 Sugarcane Bagasse 50 Algae (algal mass) 50 Algae (algal oil and lipids) 50 Notes: 1. Direct value from Integrated Supply Chain NC State University, (Daystar, J. et. al. 2012) 2. Vegetable crop residues are considered negligible for purposes of this report because the total biomass that can effectively be utilized (million dry tons/yr) is only 0.1 as represented in Table 4 1. Vegetable crop residues are not generally considered for off field utilization and are commonly incorporated into the soil, (Moller, 2005). Reference: Appendix A, Phase 2 Calculations Environmental Impact of Approving Biomass Conversion Plants in California Page 18

27 4.3 Phase 3: Transportation Transportation includes CO emissions associated with transporting the biomass fuel to the energy generation plant. The state of California has relatively low CO emissions associated with transportation of biomass feedstocks because the biomass energy industry is already well established for agricultural biomass throughout the Central Valley and for forestry biomass in Northern California. Table 4 3shows a small increase in CO emissions during the Phase 3: Transportation stage based upon the values given in Figure 4 1. Environmental Impact of Approving Biomass Conversion Plants in California Page 19

28 Table 4 3 CO 2 Emissions for Phase 3: Transportation (from Figure 4 1) Feedstock Types CO 2 Emissions for Phase 3 (kg CO 2 eq./ton) TOTAL Biomass Feedstocks 215 First Generation Feedstocks 160 Agricultural Biomass 50 Animal Manure 10 Orchard Pruning s and Vine Removal 10 Field and Seed 10 Vegetable 10 Food Processing (rice hulls, shells, and pits) 10 Forestry Biomass 60 Mill Residue 15 Forest Thinnings 15 Logging Slash 15 Chaparral 15 Municipal Biomass 50 Municipal Solid Waste 50 Second Generation Feedstocks 55 Loblolly Pine 5 Eucalyptus 5 Unmanaged Hardwood 10 Switchgrass 5 Miscanthus 5 Sugarcane/Energycane 5 Wheat Straw 5 Sugarcane Bagasse 5 Algae (algal mass) 5 Algae (algal oil and lipids) 5 Notes: 1. Direct value from Integrated Supply Chain NC State University, (Daystar, J. et. al. 2012) Reference: Appendix A, Phase 3 Calculations Environmental Impact of Approving Biomass Conversion Plants in California Page 20

29 4.4 Phase 4: Energy Generation Technology Fuel Analysis Approach for Estimating CO 2 Emissions: Using the Fuel Analysis Equation shown below, which was developed from the Environmental Protection Agency (EPA, 2008), we calculated CO 2 emissions for different energy generation technologies. Fuel Analysis Equation Emissions = Where: Fuel = Mass or Volume of Fuel Type Combusted = Average Higher Heating Value of Fuel Type ( CC = Carbon Content Coefficient of Fuel Type ( ) FO = Fraction Oxidized of Fuel Type ) = Molecular weight of C = Molecular weight of Carbon Figure 4 2 Basis for Fuel Analysis Calculations Step 1: Determine the amount of fuel combusted. This is an assumed value based on fuel used during each phase of the biomass pathway. Step 2: Convert the amount of fuel combusted into energy units. The amount of fuel combusted is measured in terms of physical units, (mass or volume). This needs to be converted to amount of fuel used in terms of energy units in order to apply the default carbon content coefficients. The heat content of various biomass fuels is provided in Tables 3 1and 3 2 columns titled Average Energy Value. Step 3: Estimate carbon content of fuels consumed. To estimate the carbon content, multiply energy content for each fuel by fuel specific carbon content coefficients (mass C / energy). U.S. average default carbon content coefficients are provided in Figure 4 1. Environmental Impact of Approving Biomass Conversion Plants in California Page 21

30 Step 4: Estimate carbon emitted. When fuel is burned, most of the carbon is eventually oxidized into CO 2 and emitted into the atmosphere. To account for the small fraction that is not oxidized and remains trapped in the ash, multiply the carbon content by the fraction of carbon oxidized. The amount of carbon oxidized is assumed to be 100% unless specific supplier information is available. Step 5: Convert to CO 2 emitted. To obtain total CO 2 emitted, multiply carbon emissions by the molecular weight ratio of (44) to Carbon (12), (44/12). Table 4 4 summarizes the results of the calculations of CO 2 emissions based on co firing, direct combustion, and gasification technologies. Each technology is calculated both with, and without, avoided emissions considered. The term w/o avoided emissions refers to the amount of CO 2 emissions that would be generated if conventional fuels were used; w/avoided emissions refers to the decrease in CO 2 emissions by using biofuels in lieu of conventional fuels. Refer to Section 5.1, Net Reduction to CO 2 emissions, for more detailed information on the effect of considering energy generation technologies both with, and without, avoided emissions. Equation 1: Fuel Analysis Approach is used to calculate total CO emissions based on a fuel content of 1 kg. Environmental Impact of Approving Biomass Conversion Plants in California Page 22

31 Table 4 4 CO 2 Emissions for Co Firing, Direct Combustion and Gasification Technologies Energy Generation Technology Co Firing w/o Avoided Emissions Co Firing w/ Avoided Emissions Direct Combustion w/o Avoided Emissions Direct Combustion w/ Avoided Emissions Gasification w/o Avoided Emissions Gasification w/ Avoided Emissions Reference Step 1 Step 2 Step 3 Step 4 Step 5 TOTAL Biomass Fuel Average Heat Content CC FO / C Emissions for Phase 4 kg kj/kg (dry) kwh/kg (dry) Kg / kwh ratio Ratio (44/12) kg eq. / ton , , , , , , , , ,380, , , , , , ,459 Value of 1kg Avg. HC (Table 1) 1 KJ/kg = 3600 kwh/kg Figure 4 1 U.S. EPA, 2008 U.S. EPA, 2008 Appendix A Environmental Impact of Approving Biomass Conversion Plants in California Page 23

32 Without avoided emissions considered, the highest value for CO 2 emissions is 621 kg CO 2 eq./ton. With avoided emissions considered, the highest value for CO emissions is 13,459 kg CO 2 eq./ton. Using the highest value of CO 2 emissions for both scenarios allows for a conservative calculation of emissions throughout the biopower pathway. 4.5 Phase 5: Timeframe to Replenish Feedstock If feedstocks are collected without regard to replenishment, or in an otherwise unsustainable manner, biopower enterprises may lead to natural resource deterioration such as soil erosion or the depletion of forested land, (Bracmort, 2010). The recognition of biomass as a renewable resource means that biomass is considered by some to be a continuous feedstock that may be replenished in a short time frame (Bracmort, 2012). The timeframe to replenish biomass feedstocks can vary depending upon market fluctuations and weather variability. A wide range of values, ranging from three (3) months to forty (40) years, has been selected for different feedstocks to consider high variability from one year to the next. The Table 4 5 lists the timeframe to replenish a feedstock and the average timeframe in years. Environmental Impact of Approving Biomass Conversion Plants in California Page 24

33 Table 4 5 CO 2 Emissions for Phase 5: Timeframe to Replenish Feedstock Feedstock Types Timeframe to Replenish Feedstock Average Timeframe (years) TOTAL Biomass Feedstock s (average) 3.5 years 3.5 First Generation Feedstock s (average) 6 months 0.5 Agricultural Biomass (average) 3 months 0.25 Animal Manure Not available, assume 1 yr 1.0 Orchard Pruning s and Vine Removal Field and Seed Vegetable Food Processing (rice hulls, shells, and pits) Forestry Biomass (average) 1 year 1.0 Mill Residue Highly variable, assume yr Forest Thinnings 1year 1.0 Logging Slash 1year 1.0 Chaparral 1year 1.0 Municipal Biomass (average) Not available, assume 1 yr 1.0 Municipal Solid Waste Not available, assume 1 yr 1.0 Second Generation Feedstocks (average) 6.5 years 6.5 Loblolly Pine Eucalyptus Unmanaged Hardwood, assume 1 yr 1.0 Switchgrass Miscanthus Sugarcane/Energycane Wheat Straw Sugarcane Bagasse Algae (algal mass), assume 1 yr 1.0 Algae (algal oil and lipids), assume 1 yr 1.0 Notes: 1. Direct value from Bracmort 2010, Appendix A 2. Assumed value from Bracmort 2010, Appendix A Reference: Bracmort 2010 Environmental Impact of Approving Biomass Conversion Plants in California Page 25

34 4.6 CO2 Emissions of the Biopower Pathway Carbon emissions for each phase of the biopower pathway are summarized in Table 4 6. Note that avoided emissions are represented as A.E. Environmental Impact of Approving Biomass Conversion Plants in California Page 26

35 Table 4 6 CO 2 Emissions of the Biopower Pathway (kg CO 2 eq./ton)* Feedstock Types Phase 1 Phase 2 Phase 3 Phase 4 Phase 4 Phase 5 TOTAL (w/a.e.) TOTAL (w/o A.E.) (w/a.e.) (w/o A.E.) TOTAL Biomass Feedstocks 34, , N/A 586,654 36,595 First Generation Feedstocks 16, , N/A 327,854 18,094 Agricultural Biomass 7, , N/A 251,778 12,418 Animal Manure 1, , ,234 1,154 Orchard Pruning s and Vine 1, , ,936 4,616 Removal Field and Seed 1, , ,936 4,616 Vegetable negligi , ,736 2,584 ble Food Processing 1, , ,936 4,616 Forestry Biomass 7, , N/A 60,917 4,597 Mill Residue 1, , ,229 1,149 Forest Thinnings , ,229 1,149 1,800 Logging Slash 1, , ,229 1,149 Chaparral 1, , ,229 1,149 Municipal Biomass 1, , N/A 15,159 1,079 Municipal Solid Waste 1, , ,159 1,079 Second Generation Feedstocks 17, , N/A 258,800 18,501 Loblolly Pine , ,800 Eucalyptus , ,800 Unmanaged Hardwood , ,185 1,105 1,750 Switchgrass , ,153 3,833 1,700 Miscanthus 1, , ,817 4,497 Sugarcane/Energycane 1, , ,407 2,247 Wheat Straw 1, , ,408 2,248 Sugarcane Bagasse 1, , ,409 2,249 Algae (algal mass) 1, , ,205 1,125 Algae (algal oil and lipids) 1, , ,204 1,124 Reference Table 3 Table 4 Table 5 Table 6 Table 6 Table 7 Add Phase 1 4 and divide 1) Daystar, J. et. al by Phase 5 Environmental Impact of Approving Biomass Conversion Plants in California Page 27

36 * There are two Totals for Table 4 6, the Total CO2 Emissions with Avoided Emissions and the Total CO2 Emissions without Avoided Emissions. The Total CO2 Emissions with Avoided Emissions is calculated by adding the total CO2 Emissions from Phase 1, Phase 2, Phase 3, Phase 4 with Avoided Emissions, and dividing the sum by Phase 5. Similarly, the Total CO2 Emissions without Avoided Emissions is calculated by adding the total CO2 Emissions from Phase 1, Phase 2, Phase 3, Phase 4 without Avoided Emissions and dividing the sum by Phase 5. The method described above is true for each individual feedstock presented in Table 4 6 (every line item that is not bold). In order to calculate the total CO2 Emissions from a group of feedstocks, (every line item that is bold in Table 4 6), the total from the individual feedstocks is added together for that category. For example, the total for Agricultural Biomass is the sum of the totals for each individual feedstock: Animal Manure, Orchard Pruning's and Vine Removal, Field and Seed, Vegetable and Food Processing. The Total for First Generation Feedstocks is the sum of the totals from Agricultural Biomass, Forestry Biomass and Municipal Biomass. The TOTAL Biomass Feedstock at the top of Table 4 6 is the sum of the totals from First Generation Feedstocks and Second Generation Feedstocks. Environmental Impact of Approving Biomass Conversion Plants in California Page 28

37 Section 5 Net Reduction to CO2 emissions and Economic Feasibility Using the carbon neutral feedstocks, the economic feasibility was determined using the feedstocks/technologies for biomass plants. Our analysis included consideration of subsidies that would increase the economic feasibility. Life cycle economic factors included costs associated with feedstock type, management and procurement, transportation, energy generation technology, and timeframe to replenish the feedstock. In 2010, California produced 71% of its own electricity; the balance was imported from the Pacific Northwest (8%) and the U.S. Southwest (21%). Natural gas is the main source for electricity generation at 53.4% of the total in state electric generation system power (CEC, 2011). California s in state electricity generation is represented in the Table 5 1. Table 5 1 California In State Electricity Generation California In State Electricity Generation Source Percentage of California In State Electricity Generation Cost as an input for Electricity Generation Natural Gas 53.4% $11.32 dollars per 1,000 cubic feet*, (U.S. Energy Information Administration, 2012) Nuclear 15.7% $0.38 per million BTU, (Combs, S. 2005) Large Hydro (larger than 30 MW) 14.6% No cost as an input for generating electricity, (Combs, S. 2005) Coal 1.7% $2.44 dollars per million BTU, (U.S. Energy Information Administration, 2012) Renewable (includes biomass, geothermal, small hydro, wind, and solar generation) *Conversion factor: 1,000 cubic feet is about 1 million BTU 14.6% $2.91 per million BTU (assumed value based on biomass consumption), (U.S. Energy Information Administration, 2012) Note that geothermal, small hydro, wind, and solar have no fuel cost as an input for generating electricity. Table 5 2 calculates the cumulative fuel cost associated with the type of electricity produced in California based upon the fuel costs shown in Table 5 1. Environmental Impact of Approving Biomass Conversion Plants in California Page 29

38 Table 5 2 Cumulative Fuel Cost Calculation based on % Electricity Produced by California Electric Power Generation Fuel Cost Calculation based on % Electricity Produced in California (in dollars per million BTU) Natural Gas 53.4% $11.32 = $6.04 Nuclear 15.7% $0.38 = $0.06 Large Hydro 14.6% $0 = $0 Coal 1.7% $2.44 = $0.04 Renewable 14.6% $2.91 = $0.42 Cumulative Fuel Cost $6.56 Table 5 3 lists the results of the calculation for the economic feasibility based upon average fuel cost in US dollars per million Btu. Environmental Impact of Approving Biomass Conversion Plants in California Page 30

39 Table 5 3 Economic Feasibility Feedstock Types Fuel Cost Average (US dollars / MMBtu) Economically Feasible? Compared with cumulative fuel cost of $6.56/MMBtu Subsidy Required? (US $ / MMBtu) First Generation Feedstocks Agricultural Biomass Animal Manure N/A N/A N/A Orchard and Vine Removal $2.84 Yes No Field and Seed $2.84 Yes No Vegetable $2.84, Yes No Food Processing $2.84 Yes No Forestry Biomass Mill Residue $1.69 Yes No Forest Thinnings $7.78 No Yes, $1.22 Logging Slash $2.92 Yes No Chaparral $2.92 Yes No Municipal Biomass Municipal Solid Waste $1.47 Yes No Second Generation Feedstocks Loblolly Pine $5.96 Yes No Eucalyptus $5.96 Yes No Unmanaged Hardwood $1.47 Yes No Switchgrass $3.51 Yes No Miscanthus $3.51 Yes No Sugarcane/Energycane $5.96 Yes No Wheat Straw $4.57 Yes No Sugarcane Bagasse $5.96 Yes No Algae (algal mass) $5.96 Yes No Algae (algal oil and lipids) $5.96 Yes No Reference: U.S. Environmental Table 10, Cumulative Compares each fuel to Table Difference Protection Agency Combined Heat and Power Partnership (2007). Fuel Cost 10, Cumulative Fuel Cost Notes: 1. Manure biogas systems are typically too small for gas treatment to be economical (US EPA Combined Heat and Power Partnership, 2007, Chapter 4). 2. Average values for crop residues, (US EPA Combined Heat and Power Partnership, 2007, Chapter 3). 3. Vegetable trimmings are not carbon neutral when avoided emissions are not considered, (reference Table 8) 4. Average value for mill residues, (US EPA Combined Heat and Power Partnership, 2007, Chapter 3). 5. Average value for forest thinnings, (US EPA Combined Heat and Power Partnership, 2007, Chapter 3). 6. Average value for forest residues, (US EPA Combined Heat and Power Partnership, 2007, Chapter 3). 7. Average value for urban wood waste, the second largest component of the MSW in 1996, (US EPA Combined Heat and Power Partnership, 2007, Chapter 4). The University of Malaysia presented a value of $0.09 US $ / MMBtu for MSW used for the production of electricity, (Rosli, 2012). 8. Average values for energy crops. Since most second generation feedstocks are not currently used as biomass in the state of California, a conservative value for energy crops has been selected based on the data provided for hybrid poplars. 9. Miscanthus and switchgrass have similar feedstock properties, the value for switchgrass has been used. Environmental Impact of Approving Biomass Conversion Plants in California Page 31

40 5.1 Net Reduction to CO2 emissions A net reduction to CO2 emissions of approximately 586,654 kg CO2 eq./ton can be achieved in the state of California when all life cycle emissions are considered. This assumes the biomass feedstocks analyzed in this report are utilized in the manner presented in Table 4 6, and includes avoided emissions. The most significant factors influencing CO 2 emissions occur in Phases 1 and 4: Phase 1, Feedstock Type is the most important contributor to CO 2 emission reductions. The feedstock type for first generation feedstocks includes fuel that currently exists, but is not currently utilized for energy production. For second generation feedstock s, the fuel is easily cultivated to be utilized for energy production. In both cases, CO 2 emissions from biomass feedstocks are significantly lower than CO 2 emissions generated from fossil fuels. The negative values for Phase 1 feedstocks represent avoided CO 2 emissions. Phase 2, Management and Procurement, and Phase 3, Transportation are very low contributors to CO 2 emissions in the state of California. This can most likely be attributed to the various biomass plants that exist throughout the Central Valley of California. Phase 4, Energy Generation Technology is arguably the most important contributor to CO 2 emissions. Energy generation technologies for 1kg of fuel can emit up to 621 kg CO 2 eq./ton for co firing, and combustion technologies without considering avoided emissions. However, these same technologies with avoided CO 2 emissions can reduce CO 2 emissions as much as 13,459 kg CO 2 eq./ton. This report considers energy generation technologies both with, and without, avoided emissions to better understand the effect of energy generation technologies in the biopower pathway. Phase 5, Time to Replenish Feedstock assumes a value over time to completely regrow the biomass feedstock so that the carbon can be recaptured and returned to the biosphere. The calculated CO 2 emissions from Phases 1, 2, 3 & 4 are added together and divided by the feedstocks replenish time. This calculates an overall CO 2 emissions value (kg CO 2 eq./ton/year) for the entire biopower pathway for each feedstock. CO 2 emissions both with, and without, avoided emissions have been considered. The only scenario that results in positive CO 2 emissions is a feedstock of vegetable trimmings without considering avoided emissions. All other feedstocks analyzed in this report result in negative CO 2 emissions both with, and without, consideration of avoided emissions. The values used in Phases 1 5 can vary depending on climate, location, and transportation methods available. Appendix A: Fuel Analysis Spreadsheet provides a methodology for Environmental Impact of Approving Biomass Conversion Plants in California Page 32

41 calculating CO 2 emissions during different phases of the biomass pathway for different feedstocks. The methodology can be applied to feedstocks that were not analyzed in this report. The unknown values required to calculate CO 2 emissions from a specific fuel include: Energy Value: Btu/lb (dry) or KJ/kg Fuel consumed: million dry tons/yr (average) Carbon Content of Fuel Consumed: kg Carbon / MMBtu These unknown values are highlighted in yellow in Appendix A, Fuel Analysis Spreadsheet and hypothetical values are used as placeholders. 5.2 Economic Feasibility Economic feasibility of biomass feedstocks is analyzed by comparing the average cost of biomass fuel to the cumulative cost of fuel from California s current energy generation technologies. The majority of electricity produced in the state of California, (54%) comes from natural gas, at a cost of $11.32 US dollars per MMBtu, (Table 5 1). Other sources of electricity come from nuclear, large hydro, renewable and coal. The percentage of each electricity source is multiplied by the fuel cost of that electricity source in order to produce a cumulative cost of fuel that considers all of California s current technologies. The cumulative cost of fuel, $6.56 US dollars per MMBtu is used as the baseline to determine whether or not biomass feedstocks are economically feasible based on the fuel cost of each biomass feedstock. Most of the first generation feedstocks, including orchard pruning s and vine removal, field and seed, vegetable trimmings, food processing (rice hulls, shells, and pits), mill residue, logging slash, chaparral, municipal solid waste were determined to have an average fuel cost below $6.56 and therefore did not require a subsidy. Several of the second generation feedstocks, including loblolly pine, eucalyptus, sugarcane/energucan, sugarcane bagasse, and algae were calculated to have a fuel cost average of $5.96 US dollars per MMBtu, which approaches the limit of $6.56 US dollars per MMBtu for economic feasibility. These biomass feedstocks may require subsidies under circumstances that vary from the analyzed conditions in this report. Forest thinnings are not economically feasible because the average fuel cost is $7.78 US dollars per MMBtu. A subsidy of at least $1.22 US dollars per MMBtu is required in order for the fuel cost of forest thinnings to be competitive with the cumulative cost of fuel, $6.56 US dollars per MMBtu. Environmental Impact of Approving Biomass Conversion Plants in California Page 33

42 Animal manure is not economically feasible because manure biogas systems are typically too small for gas treatment to be economical, (US EPA Combined Heat and Power Partnership, 2007, Chapter 4). The following table summarizes biomass feedstocks and whether a subsidy may be required: Table 5 4 Carbon Neutral Biomass Feedstocks and Subsidies No Subsidy Required Subsidy May Be Required Subsidy Required Orchard Pruning s and Vine Removal Loblolly Pine Eucalyptus Field and Seed Sugarcane/Energycane MMBtu Vegetable Trimmings Sugarcane Bagasse Algae (algal mass) Food Processing (rice hulls, shells, and pits) Algae (algal oil and lipids) Mill Residue Logging Slash Chaparral Municipal Solid Waste Unmanaged Hardwood Switchgrass Miscanthus Wheat Straw Forest thinning s $1.22 US dollars / Animal manure Subsidy unknown Environmental Impact of Approving Biomass Conversion Plants in California Page 34

43 References Adams, 2005 Baldwin, 2006 Baurer 2008 Bracmort 2012 Bracmort, 2010 Bracmort, 2011 Briggs, 2001 Brink, 2012 Campbell 2007 CEC, 2011 (Adams, et al., unpublished manuscript, FASOMGHG Conceptual Structure, and Specification: Documentation. 2005). Baldwin, S. (2006). Carbon Footprint of Electricity Generation. Parliamentary Office of Science and Technology, London, United Kingdom. Bauer, C. (2008). Life Cycle Assessment of Fossil and Biomass Power Generation Chains. Paul Scherrer Institute, Switzerland. Biomass: Comparison of Definitions in Legislation Through the 112th Congress. Congressional Research Service, Washington, DC. Biomass Feedstocks for Biopower: Background and Selected Issues. Congressional Research Service, Washington, DC. Is Biopower Carbon Neutral? Congressional Research Service, Washington, DC. Research Guidelines for Life Cycle Inventories. CORRIM Panel, College of Forest Resources, University of Washington, Seattle, WA. Brink, S. The Value of Actively Managed Forestlands, Wood Products, and Biomass for Electricity Generation for California s CO _2 Emissions Reduction Goals. < (December 26, 2012). Campbell, K. (2007). A Feasibility Study Guide for an Agricultural Biomass Pellet Company. Agricultural Utilization Research Institute and Cooperative Development Services, St. Paul, Minnesota. The California Energy Commission (2011). California s Major Sources of Energy. In State Electricity Generation (2010). < > (February 13, 2013). Environmental Impact of Approving Biomass Conversion Plants in California Page 35

44 Chum et al. Chum, H., A. Faaij, J. Moreira, G. Berndes, P. Dhamija, H. Dong, B. Gabrielle, A. Goss Eng, W. Lucht, M. Mapako, O. Masera Cerutti, T. McIntyre, T. Minowa, K. Pingoud, 2011: Bioenergy. In IPCC Special Report on Renewable Energy Sources and Climate Change Mitigation [O. Edenhofer, R. Pichs Madruga, Y. Sokona, K. Seyboth, P. Matschoss, S. Kadner, T. Zwickel, P. Eickemeier, G. Hansen, S. Schlomer, C. von Stechow (eds)], Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. Ciferno and Marano 2002 Clarke 2011 Combs, 2005 Ciferno, J., Marano, J. (2002). Benchmarking Biomass Gasification Technologies for Fuels, Chemicals and Hydrogen Production. U.S. Department of Energy, Washington, DC and National Energy Technology Laboratory, USA. Clarke, S., Eng, P., Preto, F. (2011). Factsheet: Biomass Burn Characteristics. Ministry of Agriculture, Food and Rural Affairs, Ontario, Canada. Nuclear Energy. Window on State Government. < (February 14, 2013). Daystar et al, 2012 Daystar, J., Reeb, C., Gonzalez, R., Venditti, R., Kelley, S. (2012). Integrated Supply Chain, Delivered Cost and Life Cycle Analysis of Cellulosic Feedstocks for Bio Based Energy in the Southern U.S. Department of Forest Biomaterials, North Carolina State University and American Center for Life Cycle Assessment, Tacoma, Washington. Gonzalez and Wright 2010 Heller et al, 2003 IEA 2012 Gonzalez, R., Wright, J., Saloni, D. (2010). Woody Biomass: The Business of Growing Eucalyptus for Biomass. Biomass Magazine 4, pp Heller, M., Keoleian, G., Mann, M., Volk, T., (2003). Life Cycle Energy and Environmental Benefits of Generating Electricity from Willow Biomass. Elsevier. International Energy Agency, (2012). CO _2 Emissions from Fuel Combustion: Highlights. International Energy Agency, France. Jenkins et al 1998 Jenkins, B., Baxter, L., Miles, T. Jr., Miles T. (1998). Combustion Properties of Biomass. Department of Biological and Agricultural Engineering, University of California, Davis, CA, Sandia National Laboratories, Livermore, CA, and Thomas R. Miles Consulting Engineers, Portland, OR. Fuel Processing Technology, Elsevier Science, USA. Environmental Impact of Approving Biomass Conversion Plants in California Page 36

45 Kemppainen and Shannard, 2005 Mason, 2008 Mayhead 2011 Mayhead, 2012 Miner, 2010 Moller, 2005 Morris 2008 Morris, 1999 Kemppainen, A., Shonnard, D., (2005). Comparative Life Cycle Assessments for Biomass to Ethanol Production from Different Regional Feedstocks. Department of Chemical Engineering, Michigan Technological University, Houghton, MI Mason, Tad, TSS Consultants, (2008). Biomass Power Plant Development in California, Overview and Lessons Learned. Renewable Energy Conference for California Tribes. Gareth Mayhead, unpublished list of California Biomass Power Plants, May 10, Mayhead, G., Tittmann, P. (2012). California Agriculture: Uncertain Future for California s Biomass Power Plants. Volume 66, Number 1. R. Miner, Biomass Neutrality in the Context of Forest based Fuels and Products, USDA Bioelectricity and GHG Workshop, Washington, DC, November 15, Some of the definitions are not mutually exclusive. Moller, R. (2005). Brief on Biomass and Cellulosic Ethanol. California Research Bureau, Sacramento, CA. Morris, G. (2008). Carbon Footprint for Snowflake Biomass Power. Futures Resources Association Incorporated, Berkeley, California. Morris, Gregory, (1999). The Value of the Benefits of U.S. Biomass Power. Golden, CO: National Renewable Energy Laboratory. Morris, 2002 Morris, Gregory, (2002). Biomass Energy Production in California 2002: Update of the California Biomass Database. Golden, CO: National Renewable Energy Laboratory. Morris, 2003 NALC Morris, Gregory, (2003). The Status of Biomass Power Generation in California. Golden, CO: National Renewable Energy Laboratory. Biomass Research and Development Initiative. Increasing Feedstock Production for Biofuels: Economic Drivers, Environmental Implications, and the Role of Research. National Agricultural Library Cataloging Record, United States. Environmental Impact of Approving Biomass Conversion Plants in California Page 37

46 Navigant, 2006 NCDAR 2009 Overeah et al 2004 Riston and Sochacki 2002 Rosli, 2012 Sedjo, 2011 Stanford 2005 Stubbs, 2010 Navigant Consulting, (2006). Recommendations for a Bioenergy Plan for California. Bioenergy Interagency Working Group, Governor Arnold Schwarzenegger. North Carolina Division of Air Quality, (2009). Greenhouse Gas Emission Guidelines: Stationary Combustion Sources. North Carolina Department of Environment and Natural Resources, Raleigh, North Carolina. Overend, R., David, M., Perlack, R., Foust, T. (2004). Biomass Feedstocks. National Renewable Energy Laboratory. Golden, CO. Perlack, R., Wright, L., Turhollow, A., Graham, R., Stokes, B., Erback, D. (2005). Biomass as Feedstock for a Bioenergy and Bio products Industry: The Technical Feasibility of a Billion Ton Annual Supply, Oak Ridge National Laboratory, Tennessee. Ritson, P., Sochacki, S. (2002). Measurement and Prediction of Biomass and Carbon Content of Pinus Pinaster Trees in Farm Forestry Plantations, South Western Australia. Department of Conservation and Land Management, Cooperative Research Centre for Greenhouse Accounting, Kensington, WA, Australia. Forest Ecology and Management, Elsevier Science, Australia. Rosli, M. (2012). Combined Heat, Hydrogen, and Power (CHHP) Systems for a University Campus using Local Resources. National University of Malaysia. Sedjo, Roger, (2011). Carbon Neutrality and Bioenergy: A Zero Sum Game? Resources for the future, Washington, DC. Stanford University (2005). An Assessment of Biomass Feedstock and Conversion Research Opportunities, Global Climate and Energy Project, Stanford University, California Stubbs, Megan, (2010). Biomass Crop Assistance Program (BCAP): Status and Issues. Congressional Research Service. UITP, 2012 Intergovernmental Panel on Climate Change (2009). Calculating CO 2 Emissions. < (December 26, 2012). USDA, 2005a United States Department of Agriculture, Forest Service, (2005). Forests to Electrons: Costs and Benefits of Using Wildland Biomass to Generate Electrical Power. Pacific Southwest Research Station. Environmental Impact of Approving Biomass Conversion Plants in California Page 38

47 USDA, 2005b USEIA, 2012 USEPA 2007 USEPA, 2007 USEPA, 2008 United States Department of Agriculture, Forest Service, (2005). Life Cycle Assessment: Using Wildland Biomass to Generate Electrical Power. Pacific Southwest Research Station. United States Energy Information Administration (2012). Short Term Energy Outlook. < > (December 27, 2012). United States Environmental Protection Agency Combined Heat and Power Partnership (2007). Biomass Combined Heat and Power Catalog of Technologies: Power Generation Technologies, pp United States Environmental Protection Agency Combined Heat and Power Partnership (2007). Biomass Combined Heat and Power Catalog of Technologies: Biomass Resources, pp United States Environmental Protection Agency, Greenhouse Gas Inventory Protocol Core Module Guidance: Direct Emissions from Stationary Combustion Sources. Climate Leaders, Office of Air and Radiation, Washington, DC., Walker, 2010 Walker, T., USDA Bioelectricity and GHG Workshop, oral presentation Manomet & Biomass: Moving Beyond the Soundbite, Washington, DC Environmental Impact of Approving Biomass Conversion Plants in California Page 39

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49 APPENDIX A Calculation Spreadsheets Fuel Analysis Spreadsheet Emissions = Unknowns (hypothetical values used) Environmental Impact of Approving Biomass Conversion Plants in California Page 41

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51 Phase 2 Calculation Spreadsheet Emissions = Environmental Impact of Approving Biomass Conversion Plants in California Page 43

52 Phase 3 Calculation Spreadsheet Emissions = Environmental Impact of Approving Biomass Conversion Plants in California Page 44